IDIS GI Inflammatory Infections of the Intestine Flashcards
Pseudomembranous colitis, look for yellowish plagues on colonoscopy
C. difficile
Fulminant colitis, usually diarrhea, diffuse severe abd pain, hypoactive bowel sounds, abd distension and guarding, marked peripheral blood leukocytosis, complications: perforation and toxic megacolon
C. difficile
What is the most sensitive test for detecting C. difficile?
PCR or glutamate dehydrogenase screen of fecal sample
What are the 3 most common causes of invasive gastroenteritis? Other causes?
Campylobacter (most common overall), Shigella, Salmonella
Others: EHEC, EIEC, Yersinia enterocolitica, Entamoeba histolytica
Which E. coli should NOT be treated with antibiotics?
EHEC- you will increase the risk for kidney damage
Leading cause of bacterial diarrheal disease. Cattle, chickens, birds, and flies. Found in non-chlorinated water. Acquired from undercooked or raw meat, unpasteurized milk.
Campylobacteriosis
Hard to grow, s-shaped (seagull shaped), darting motility in watery and bloody leukocyte-filled stool
Campylobacter jejuni
Special test for campylobacteriosis?
Campy-BAP or Skirrow media
From contaminated water sources, problem in daycare nursing homes prisons, can be spread by the 4 F’s (food, fingers, feces, flies)
Shigellosis
What are the two most common Shigella species in the US?
S. sonnei and S. flexneri
Nonmotile, no lactose fermentation, gram-neg rod, resistant to stomach acid
The toxin shuts down protein synthesis leading to cell death, it uses host actin to move from cell to cell
Shigella
What is the special way of diagnosing shigellosis?
growth on S-S agar
fecal leukocytes will be present
Motile, nonlactose fermenting rod, enteric fevers- person to person from chronic carriers
Salmonellosis
6-48 hrs after ingesting contaminated food you will have nausea, abd cramps, vomiting, non-bloody diarrhea
Other Sx- fever, HA, myalgia
Salmonellosis
EIEC
enteroinvasive E. coli
EHEC
enterohemorrhagic E. coli - has shiga toxin
Severe crampy abd pai, watery diarrhea followed by bloody diarrhea, no fever, HUS triad (acute renal failure, thrombocytopenia, microangiopathic hemolytic anemia)
EHEC
Watery diarrhea that can on occasion result in dysenteric stools, little to no fever
EIEC
Gram neg. rod, no lactose fermentation, urease positive, motile at 25 degrees celsius, not at 37 degrees celsius, can grow at 4 degrees but prefers 25-28 degrees celsius, Bull’s eye appearance on CIN agar
Yersinia enterocolitica
Subacute onset diarrhea, occasional blood stools, abd pain RLQ, fever, nausea, vomiting, PHARYNGITIS, 12-22 days, speticemia can develop into septic shock
Yersinia enterocolitica
Pseudoappendicitis, post-infectious sequelae
Yersinia enterocolitica
Pathognomonic sign for this parasite-trophozoites with intracytoplasmic RBCs
Amebiasis (Entamoeba histolytica)
Incubation 1-5 days, diarrhea, abd cramps, vomiting, tenesmus, stools can be watery or dysenteric
Amebiasis
What creates flask-shaped ulcers?
amebiasis
What has an anchovy paste appearance in aspirations of the liver?
amebiasis
You will see parasite in feces, leukocytosis in peripheral blood smear, CXR will show extra-intestinal infections
amebiasis
